You have two issues: fast data access for day to day, reachable from anywhere, and insurance against catastrophic loss like drive failure, fire/theft.
What about a “belt-and-suspenders” approach? Such as: daily backups go to Cloud-based storage, and a weekly backup “ghosting” of the whole RAID goes onto hard drives, one of which can stay on-site, in rotation with three offsite back-ups? Once you have the computers set up to automate the backup process on a regular schedule, you can mostly forget about it.
It may help to imagine a couple of “worst case” scenarios, then design your methods and tech to answer that problem.
Worst case 1: in-house RAID failure, on the clock, deadline looms. What’s a faster/practical restore situation, I’d say cloud, *if* you have high bandwidth so it doesn’t take all day.
Worst case 2: can’t work from the shop, can you access remotely from home or another studio space?
If you’re doing incremental back-ups, what’s the maximum loss you’re comfortable with, in terms of how often the backups are made? Can you stand to lose the last hour of edits? The last three? A day’s worth?
Then there’s the “U-Boat” clients: they surface sporadically, without warning, asking for cr@p you did for them two years ago, pronto. How fast should you need to be able to restore/dub files for these guys? Is a day all right?